Re: Oracle & RAID strategy question

the LVM handles the low level I/O spread and generally provides comparable performance as if you manually tuned the layout, particularly since you have only two controllers and 4 disks per controller.

i recommend using an LVM such as Veritas to manage the 4 primary disks on one controller which are then mirrored by the other four disks on the other controller.

keep in mind that oracle allocates space on a logical level, not a physical level. the LVM optimizes I/O at the physical layer. it is also easier for the DBA to manage since you are given "a big chunk of space" to work with and leave the details to the system.

steve long
"The world's best technology strategist." (TM)

"Kate Kwiatek" <kkwiatek_at_mediaone.net> wrote in message news:3AD9CD59.A55E27A3_at_mediaone.net...
> Greetings....
>
> I have a Sun E450 to configure for some small Oracle databases that will
> reside on the system. The system has 8 36-Gig hard drives and 2
> controllers. For now, the Oracle databases are fairly small and not real
> write-intensive at all. One of the databases is the database for our
> Oracle Portal application and the other database will hold financial
> information for a third-party forecasting and reporting tool called
> Control8 (KCI Computing). I'm not the actual unix sys admin who will be
> configuring the box, but the Oracle DBA driving the general
> configuration request.
>
> My dilemma is that I'm torn between which implementation of software
> RAID i should have the sys admins build. We must have complete
> redundancy so 4 disks will definitely be mirrored -- an unfortunate
> overhead, but my company can afford it. The two choices I have are the
> following:
>
> 4 disks each individually mirrored and manually laying out my Oracle
> directories to separate data, indexes and database software...
>
> or
>
> 2 logical volumes(4 disks-1controller each) striped and mirrored with an
> LVM like Veritas Volume Manager
>
> The problem I have with the second option is that I cannot directly
> control the separation of data and indexes in the Oracle environment,
> but since the databases are small and not highly-transactional, I am
> thinking the disk i/o benefit from the striping alone will negate this
> issue.
>
> Does anyone have any advice on which setup I should go with?? I
> understand the implications of failures for each, so I'm really just
> wondering which would offer better read-write performance for my
> particular database environment.
>
> I appreciate all advice....much thanks to all who reply:)
>
> Sincerely,
>
> Kate Kwiatek
> Manager - Technical Control
> Raytheon Company
> kwiatek_at_raytheon.com
>
>
Received on Sun Apr 15 2001 - 12:18:55 CDT